1. Field
One or more example embodiments relate to a zoom lens system, and more particularly, to a three-group zoom lens system.
2. Description of the Related Art
Recently, there has been increasing demand for reducing or minimizing the size of imaging apparatuses such as digital cameras, video cameras, and surveillance cameras.
However, to attain high-resolution imaging devices such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) included in an imaging apparatus, it is advantageous for such an imaging device to have a large area and to include a greater the number of pixels. Accordingly, a size of an optical system focusing light on the imaging device may also increase, and aberrations of the focused light throughout the entire area of the imaging device need to be reduced. Therefore, demand has increased for a high-performance zoom lens system mounted in a small-sized imaging apparatus and capable of focusing light of small aberration throughout the entire area of the imaging device.
Also, as the importance of security has recently increased, a surveillance camera or a precision measurement camera for closed-circuit television (CCTV) has become more widely used by individuals, as well as public organizations or companies. Because a surveillance camera is used at night as well as during the day, a zoom lens system used in a surveillance camera needs to be capable of correcting aberrations from a visible ray region to a near-infrared ray region, and should have a smaller F-number, in order to obtain clear images with less noise even in an environment of low light intensity.